1. Field of the Invention
The present invention relates to color photographic light-sensitive materials. More particularly, the present invention relates to silver halide color photographic light-sensitive materials containing a precursor of a color developing agent.
2. Description of the Prior Art
A general process for forming color images comprises developing silver halide photographic light-sensitive materials using an aromatic primary amine developing agent in the presence of color couplers having the ability to form dyes by reacting with an oxidation product of the developing agent to form azomethine or indoaniline dyes. This color development process which was invented originally by L. D. Mannes and L. Godowsky in 1935 and which has been improved has now been used widely all over the world in the photographic field.
The processing of color photographic light-sensitive materials consists essentially of the following three steps:
(1) a color development step, PA0 (2) a bleaching step, PA0 (3) a fixing step.
The bleaching step and the fixing step may be carried out at the same time. Namely, a bleaching step (the so-called blix step), by which developed silver and undeveloped silver halide are removed can be used. In actual development processing, auxiliary steps for maintaining the photographic or physical quality of the images formed or for improving the storage stability of the images, etc. are employed in addition to the above described two essential steps consisting of color development and silver-removal. For example, baths such as a hardening bath for preventing an excessive softening of the light-sensitive layers during processing, a stopping bath for effectively stopping the development reaction, a stabilizing bath for stabilizing the images formed or a defilming bath for removing a backing layer on the support can be employed.
Usually, the aromatic primary amine developing agents are dissolved in an aqueous alkaline solution and used as a color developing solution. If the aromatic primary amine developing agent is incorporated in the light-sensitive material, the development can be carried out using only an aqueous alkaline solution. Consequently, the developing solution can be easily prepared and the composition of the developing solution changes to a lesser extent, so that handling of the developing solution can be easily carried out. Further, there are many advantages that the BOD of the waste liquor is decreased markedly and treatment of the waste liquor is easy. However, incorporation of an aromatic primary amine developing agent into a light-sensitive material, generally, has not be practically utilized yet, because many disadvantages such as desensitization of the light-sensitive material during storage, occurrence of fog or stains, or insufficient color formation in the processing, etc. occur.
Black-and-white developing agents such as hydroquinone or catechol, etc. can be incorporated into the light-sensitive materials in a comparatively stable state. For example, U.S. Pat. No. 3,295,978 discloses that these developing agents can be incorporated into the light-sensitive material as metal complex salts. On the other hand, aromatic primary amine developing agents are difficult to incorporate into the light-sensitive materials in a stable manner because of their lack of stability.
Prior art methods for incorporating aromatic primary amine developing agents into light-sensitive materials, are known. For example, U.S. Pat. No. 3,342,599 describes the use of Schiff bases of aromatic primary amine developing agents with salicylaldehyde as precursors of developing agents. U.S. Pat. No. 3,719,492 discloses the use of a combination of metal salts such as lead or cadmium salts with aromatic primary amine developing agents. In British Pat. No. 1,069,061 and U.S. Pat. No. 2,930,693, phthalimide type precursors prepared by reacting aromatic primary amines with phthalic acid are used. Additional known methods are described in German Pat. No. 1,159,758 and U.S. Pat. Nos. 3,419,395 and 3,705,035. However, all of the requirements of a formation of sufficient color density on development, a lack of desensitization on storage of the light-sensitive materials and the elimination of the occurrence of fog or stains can not be obtained using any of these prior art means.